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A128345
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Numbers k such that (8^k - 5^k)/3 is prime.
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19
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OFFSET
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1,1
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COMMENTS
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All terms are primes.
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LINKS
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MATHEMATICA
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k=8; Do[p=Prime[n]; f=(k^p-5^p)/(k-5); If[ PrimeQ[f], Print[p] ], {n, 1, 200}]
Select[Range[5000], PrimeQ[(8^#-5^#)/3]&] (* Harvey P. Dale, Mar 23 2011 *)
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PROG
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CROSSREFS
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Cf. A062572, A128344, A128346, A128347, A128348, A128349, A128350, A128351, A128352, A128353, A128354.
Cf. A057171, A082387, A122853, A128335, A128336, A128337, A128338, A128339, A128340, A128341, A128342.
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KEYWORD
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hard,more,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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